1. Field of the Invention
The present invention relates to a positioning system in which a plurality of terminal equipments are connected by way of a communication network, and a terminal equipment can detect the present position of other terminal equipment.
2. Description of Related Art
FIG. 20 shows an example for the constitution of a positioning system of the prior art. In the positioning system, user A has portable remote terminal 11A and GPS (Global Positioning System) device 12A connected with terminal equipment 11A. In the same manner, other user B has portable remote terminal 11B and GPS device 12B connected with portable remote terminal 11B.
Portable remote terminals 11A and 11B are enabled to conduct radio communication between each other by way of radio communication network 13. The GPS devices 12A, 12B receive radiowaves outputted from a plurality of low earth orbit satellites 10A, 10B (usually by the number of three or more although illustrated by two in this embodiment), and the present positions of each of the terminals is determined by calculation.
When user A intends to recognize the present position of user B for instance, user A calls to portable remote terminal 11B of the user B by way of radio communication network 13 (telephone). Then, user A asks user B to inform the present position by telephone (voices).
Upon receiving the request, user B reads the present position from GPS device 12B and informs the read present position to user A by telephone (voices).
The procedures are the same when user B intends to recognize the present position of user A.
In the positioning system of the prior art, since each of the users informs the present position by the voices, it is difficult to recognize an accurate position of the mating terminal.
Further, since portable remote terminal 11A or 11B for informing the present position to the mating terminal and GPS device 12A or 12B for detecting the present position are provided separately, they have to be carried about individually, which makes the device larger in the size and inconvenient to carry about.
The present invention has been accomplished in view of the foregoing situations and it is an object of the invention for simply recognizing the present position of other user and avoiding the enlargement for the size of the device.